Adds entity_flame ID to Angelic (#1202)

src/main/java/com/gtnewhorizons/angelica/mixins/Mixins.java

@@ -182,6 +182,7 @@ public enum Mixins implements IMixins {
             , "shaders.MixinLocale"
             , "shaders.MixinOpenGlHelper"
             , "shaders.MixinRender"
+            , "shaders.MixinRenderEntityFlame"
             , "shaders.MixinRendererLivingEntity"
             , "shaders.MixinRenderGlobal"
             , "shaders.MixinTileEntityBeaconRenderer"

src/mixin/java/com/gtnewhorizons/angelica/mixins/early/shaders/MixinRenderEntityFlame.java

@@ -0,0 +1,37 @@
+package com.gtnewhorizons.angelica.mixins.early.shaders;
+
+import it.unimi.dsi.fastutil.objects.Object2IntFunction;
+import net.coderbot.iris.block_rendering.BlockRenderingSettings;
+import net.coderbot.iris.shaderpack.materialmap.NamespacedId;
+import net.coderbot.iris.uniforms.CapturedRenderingState;
+import net.minecraft.client.renderer.entity.Render;
+import net.minecraft.entity.Entity;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Unique;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
+
+@Mixin(Render.class)
+public class MixinRenderEntityFlame {
+    @Unique
+    private static final NamespacedId flameId = new NamespacedId("minecraft", "entity_flame");
+    // Shader devs use entity_flame to target this effect.
+    
+    @Inject(method = "renderEntityOnFire", at = @At("HEAD"))
+
+    // This runs after the initial entity has finished being rendered.
+    // The flame is not a real entity but from the shader's perspective, it is.
+    private void iris$setFlame(Entity entity, double x, double y, double z, float partialTicks, CallbackInfo ci) {
+        Object2IntFunction<NamespacedId> entityIdMap = BlockRenderingSettings.INSTANCE.getEntityIds();
+        if (entityIdMap != null) {
+            CapturedRenderingState.INSTANCE.setCurrentEntity(entityIdMap.applyAsInt(flameId));
+        }
+    }
+
+    @Inject(method = "renderEntityOnFire", at = @At("RETURN"))
+    private void iris$resetFlame(Entity entity, double x, double y, double z, float partialTicks, CallbackInfo ci) {
+        CapturedRenderingState.INSTANCE.setCurrentEntity(0);
+    }
+
+}